Soybean lecithin-stabilized oil-in-water (O/W) emulsions increase the stability and in vitro bioaccessibility of bioactive nutrients

This study was proposed to investigate the possibility of co-delivering essential oils and lipophilic nutrients via lecithin stabilized emulsions. Emulsions with different droplet sizes (62.5–105 nm), zeta potentials (−33.7 to −58.6 mV), and PdI values (0.155–0.275) were successfully prepared. Incorporation of curcumin into emulsions significantly improved its water solubility (1700-fold), thermal and photochemical stability. The droplet size of curcumin-loaded emulsions did not change over 30 days of storage at 4 °C. Gastrointestinal tract (GIT) digestion caused significant changes in the droplet size and interfacial properties of curcumin-loaded emulsions. The bioaccessibility of encapsulated curcumin was 4.79–10.6-fold higher than that of free molecule. This is mainly attributed to the different solubility of curcumin in essential oils, which also showed different bioaccessibility. The findings suggested that emulsions can be novel carriers for co-delivering essential oils and lipophilic nutrients with increased stability and bioaccessibility.